Chinese Environmental Officials to Stop Counting ‘Blue Sky Days’

Chinese authorities say they will no longer use the imprecise method of counting “blue sky days” as a measure of air quality in the country's heavily polluted capital city.

The state-run China Daily newspaper on Wednesday quoted a senior environmental official in Beijing as saying that the measurement was “only an average figure and can hardly reflect the specific situation” of pollution in the city.

A report released earlier this week found that Beijing enjoyed 286 “blue sky days” in 2011. But the official said that it would be the last such report issued, acknowledging the figures were “always different” from the feelings of the general public.

China has made recent efforts to improve its air quality readings following a public outcry that it was understating pollution levels.

The Chinese capital now releases data based on smaller particles known as PM2.5 – particles that measure 2.5 micrometers or less, which scientists say are among the most dangerous because they are able to lodge themselves into lungs.

But the rest of the country only bases air quality data on particles of 10 micrometers or larger, known as PM10, and does not take into account the smaller, more harmful particles.

In 2009, the U.S. Embassy in Beijing began posting its own hourly PM2.5 air quality data on its Twitter page, which has since attracted over 19,000 followers.

But on Tuesday – coincidentally the United Nations World Environment Day – a senior Chinese environmental official demanded that foreign embassies stop posting the readings, saying they represent an unacceptable interference in Chinese affairs.

Vice Environment Minister Wu Xiaoqing said only the Chinese government has the authority to publish such readings. But he declined to say what actions the government would take if foreign embassies did not stop publishing them.